Kiln construction



Patented Oct. 14, 1924.

UNITED STATES PATENT OFFICE.

IENOCH P. STEVENS, OF CHICAGO, ILLINOIS; MARY ANN STEVENS EXECUTRIX O'FSAID ENOCH P. STEVENS, DECEASED.

KILN CONSTRUCTION.

Application filed November 16, 1922.

To all whom t may concern.'

Be it kno-wn that I, ENocH l?. STEVENS, a citizen of the United States,residing at Chicago, in the county of Cook and State of Illinois, haveinvented certain new and useful Improvements in Kiln Constructions, ofwhich the following isa specification.

The present invention relates to kiln construction.

An object of the present invention is to provide a kiln in which thedistribution of heat may be readily controlled.

A further object is to provide a kiln of novel construction involvingmeans for conducting air in proximity to heated parts of fthe kiln andwhereby the operation of said kiln may be conveniently controlled.

A further object is to provide a kiln having means for supplyingproducts of combustion and means for efficiently preheating air formixture with said products of combustion, said kiln being readilycontrollable for distributing the heat and so constructed that cleaningand repairs may pe accomplished without shutting down the iln.

A further object is to provide a kiln with improved combustion meanswhereby repairs and cleaning of the fire box may be accomplished withoutshutting down the kiln.

Further objects will appear as the description proceeds.

Referring to the drawings Figure 1 is a sectional view of a kilnembodying the principles of the present invention;

Figure 2 is a sectional view taken on the plane indicated by the arrows2-2 of Figure 1;

Figure 3 is a sectional view taken on the plane indicated by the arrows3-3 of Figure 1. y

The numeral 1 indicates the wall of a kiln, which wall may be ofcircular construction, said wall 1 being surmounted by the dome 2.Placed preferably centrally of the wall 1 is the flue 3, which comprisesan upstanding cylindrical member having co-axial walls 4 and 5. Theinner wall 4 Serial No. 601,206.

provides a passageway for products of combustion and the walls 4 and 5provide between them an annular space 6 for air. rlhe wall 5 is providedwith` apertures 7-7 near the top of said wall, which apertures theescape of gases therethrough. Mounted beneath said Hoor 9 is the baiiiewall 1() for directing gases toward the periphery of the kiln, wherebyto aid in the even distribution of the heat within thekiln. Below thebaflie wall 10 are a number of passageways, one of which is indicated bythe numeral 11, which communicate with the stack tunnel 12.

Leading to the flue 3 is a conduit 13 which formsa passageway 14 forgases produced in the fire box 15. A substantially level surface of fuelin the fire box 15 may be maintained by means of the push rod 16, whichmay be operated at intervals by the gearing 17, which may be driven inany preferred way. The numeral '18 indicates a supply of fuel from whichdelivery may be made as desired. The conduit 13 also providespassageways 19-19 communicating with the annular space 6 in the flue 3.Said passageways 1.9-19 carry air to said annular space 6 from theopening 20. By reason of the fact that the passageways 19-19 arearranged in proximity to the passageway 14 vand heated gases passingtherethrough, said air will be preheated, whereby a high temperaturemaybe maintained Within the kiln.

The fire box 15 is provided with a grate 21 of any preferredconstruction. According to the present invention, air is admit-ted ytoin distinct passageways to different sections of said grate, saidpassageways extending from front to rear of the grate. In the heatingsaid air. Air in duct 25 will ,prefer-l ablybe under pressureandv willbe connected Vto the various compartments 23-23 below the grate 2l. Onemethod of distributing the air into the compartments 23 23 isillu'strated in the drawing. A header 26 may beprovided from whichbranch pipes 27-27 lead to the individual compartments 2,3, each of thebranch pipes being individually controlled, as, for example, by a valve28.

' The header 26 communicates with the duct 215` through a connection 29,a fragment of which is illustrated in Figure 2. Air for the opening 2Oand passageways 19 may be taken from the header 26', a suitable, valve26 being provided for controlling. the pressure of the air in saidpassages 19-19 and apertures 7-7 of the flue 3.

In operation,y the push rod 16 will be operated at intervals to maintaina substantial level of fuel. in the fire box l5. Air for the kiln willpass through duct 25, being heated dueto its proximity to the kiln, andwill pass through connection 29, header 26 and branch pipes 27-27 to thevarious compartments' 2,3-23.v The air entering said compartments Willsupport combustion in the fire box l5 and gases will pass throughpassagevvay letv to the flue 3, striking the baffle plate 8, `Where saidgases Will be deflected laterally. Air under pressure Will pass throughthe passageways v1.9-19 of the conduit 13 to the annular space 6in theflue 3, issuing fromsaid space 6through the apertures7-7 in a directioninclined to the vertical. Said air will project the gases from flue 3toward the top and toward the cylindrical vvallof the kiln. Bycontrolling the pressure in the passageways 19 and annular space 6, theforce` with which thel air and gases are projected from the flue may becontrolled. By means of this control the distribution of the heat'within the kiln may be accomplished with improved uniformity. pByfreason of the distribution ofl air from duct 2 5 ,tol the variouscompartmentsI 23-23 under" the grate 2 1, it is possible to control,

individually, theair supply to the various sections ofthe grate. If' itshould loe found necessaryor desirable to repair orclean any of:saidsectio'ns ofthe lire or' grate, the sup- `the necessary operatingtemperature.

ply of air may be shut oft' from the corresponding compartment and thefire drawn from that section of the grate, whereby the repairs orcleaning may be made without drawing the lire from the remainder of thegrate. Y

The importance of this feature from a practical standpoint may beexplained as follows: It is desirable toV attain and maintain a certainpredetermined temperature Within the kiln.A Due to imperfect fuel orotherffactors, the lire is very likely to become fouled with clinkersorother objectionable matter. ln order to clean the fire, it has beennecessary in prior practice to draw the fire in the fire 'box, therebyallowing the temperature in the kiln to drop several hundred degrees.After the fire has been cleaned, a. long period of time, amounting tomany hours, is required to bring the temperature of thel kiln vback tothe requiredoperating'temperature. According to this prior practice,many hours of time and labor are lost and, in addition, a great amountof fuel is consumed in bringingthe temperaltureback from the reducedtemperature to Accordingvto the present invention, however, the airsupply to one of the compartments 23 may be shut od and the firev inthat sec-l tion of the grate drawn and cleaned, ,the other sectionsbeing kept in operation tfmaintain the temperature in the kiln at thedesired degree. rThe section of the lire above each compartment may becleaned in this way without allowing the temperature to drop a materialamount. Time, labor. and fuelv are all conserved to a very materialextent. f

' A further advantage of the present inven-l tion lies in the fact thata better control may be had within the Vkiln during the process ofdrying, or water-smoking, the green brick. When the green brick areplaced in the kiln they Will ordinarily contain an excess of moisture,which moisture should b e driven off at a relatively low temperature.'Too high a temperature at this stage is destructive to the green brick.According to the ico ic .is

present invention, during the early stages j :i

of the brick treatment fire may be v maintained inless than all of thesections above the chambers 2323, and air under pressure Will be passedthrough the' other .sections, y whereby a strong draft is maintained,though the temperature in the kiln is kept 'at a point below that Whichwill be destructive to green brick. The stron'gdraft will drive oft' themoisture from the green brick, leaving said brick in condition toreceive the high temperatures required fork the complete heat treatment.v

vOne embodiment of the present invention has been described iny detail.Many modifications Will occur to those skilled in the art.

It is intended in this patent to cover all such modifications that fallwithin the scope of the invention as deined by the appended claims.

l claim:

l. A kiln, comprising an upstanding flue providing a chamber for thepassage of gases and a space surrounding said chamber for the passage ofair, said flue being provided with means for directing said gaseshorizontally and means for directing said air at an angle inclined tothe vertical.

2. A kiln, comprising a flue having concentric walls, the inner ot saidwalls providing a space for the passage of gases, said walls providingbetween them a space for the passage of air, the outer wall beingprovided with apertures for deflecting air at an angle inclined to thevertical.

3. A. kiln, comprising a cylindrical chamber, an upstanding flue locatedwithin said chamber. centrally thereof, means for conducting heatedgases to said flue and for discharging same into said chamber, said fluehaving means providing a passageway for air, said last mentioned meansbeing provided with apertures for directing said air at an angleinclined to the vertical.

4l. A kiln, comprising aI cylindrical chamber, an upstanding fluelocated therein, said flue having a. central passageway and an annularpassageway separated from but surrounding said central passageway, aconduit forming a passageway for conducting gases to said centralpassageway, said conduit having another passageway leading to saidannular passageway, and means for controlling the pressure of air insaid annular passageway.

A kiln, comprising a cylindrical chamber, an upstanding flue locatedtherein, said flue having a central passageway and an annular passagewayseparated from but surrounding said central passageway, a conduit forconducting gases to said central passageway, said conduit having anotherpassageway leading to said annular passageway, and means for controllingthe pressure of air in said annular passageway, means being provided fordirecting air from said annular passageway in a direction inclined tothe vertical.

6. Kiln construction, comprising heating chamber, a fire box forproducing gases for said cham-ber, said fire box being provided with agrate, means for conducting air to the space below said grate, meansdividing said space into a plurality of compartments divided along linesextending from Jfront to rear of the grate, said conducting meanscomprising a plurality ot independently controllable conduits.

7; Kiln construction, comprising a heating chamber, a fire box forproducing gases for said heating chamber, said fire box having a grate,walls extending Jfrom iront to rear out said grate, said walls formingcompartments for conducting air to sections ot said grate, and conduitsfor leading air individually to said compartments, said conduits beingindependently controlled.

8. A kiln comprising an upstanding Hue providing a. chamber for thepassage of gases and a space surrounding said chamber for the passage ofair, fire boX, and a conduit tor directing gases from said tire box tosaid chamber, means being provided for conducting air to said space, anair duct thermally associated with said kiln whereby air in said. ductmay be heated by heat conduction from said kiln. said conduit andconducting means having communication with said air duc-t, and meansJfor selectively controlling the supply of air Jfrom said air duct tosaid conduit and said conducting means.

9. A. kiln comprising a cylindrical chamber, an lupstanding flue locatedtherein, said flue having a central passageway and an annular passagewayseparated from but surrounding said central passageway, a conduit torconducting gases to said central passageway, said conduit having anotherpassageway leading to said annular passageway, an air duct in thermalassociation with said chamber whereby air in said air duct is heated byconduction from said chamber, said air duct having communication withsaid conduit and said other passageway, and means for individuallycontrolling the passage ot air from said air duct to said conduit andsaid othery passageway.

l0. A kiln comprising a grate having a plurality ot independentlycontrolled sections, a cylindrical chamber, an upstanding flue locatedthereinsaid flue having a. central passageway and an annular passagewayseparated from but surrounding said central passageway, a conduit forconducting gases from said grate to said central passageway, saidconduit having another passageway leading to said annular passageway. anair duct thermally associated with said chamber whereby air in said ductis heated by conduction from said chamber, means for controlling thepressure of air in said other passageway, and means for controlling thepressure of air in said conduit, said last mentioned means includingindividually controllable air inlet means for the various sections ofsaid grate.

ll. A kiln construction comprising a heating chamber, a fire box forproducing gases tor said chamber, said lire box being provided with agrate, means for conducting air to the space below said grate, meansdividing said space into a plurality of compartments divided along linesextending from front to rear of the grate, said heating chamber lbeingprovided with' a flue havpressure of the air supplied from said air duetto said oondioting'means and to lsaid othei1 passageway.

Signed at Chicago, Iliinois, this 13th day of November, 1922i ENOCH P.STEVENS.

